This application claims benefit of priority to Australian Patent Application PQ5729 filed on Feb. 18, 2000, and International Patent Application No. PCT/AU01/00168 filed on Feb. 19, 2001 to Spiros Michaclidis and Constantine Michaelidis, each of which applications are incorporated by reference.
The present invention relates to a sign display panel assembly which is able to efficiently illuminate an entire surface area of a display or sign held thereon.
More particularly, the present invention relates to a sign display assembly having at least one single line matrix applied to a transparent substrate through which light may be transmitted for the purpose of evenly illuminating a display or sign placed on the substrate.
Illuminated display panels are known. Generally an illuminating display system comprises a transparent panel upon which at least one surface of the panel there has been imprinted a series of lines or dots usually by way of screen printing.
The prior art has generally attempted to increase the extent of illumination across one surface of a panel, however these attempts have been unsuccessful and non-economic particularly when applied to large surface areas.
In one such prior art attempt at least one planar surface of a transparent sheet has a matrix of dots applied thereon. The disadvantage of the system of dots is that the dots do not enable sufficient transmission of light for even illumination of a surface, and that in order to obtain desirable luminosity using dots a significantly thicker substrate is required giving rise to cost and weight escalation.
In even further prior attempts there has been disclosed illuminating display assemblies which include a panel, a light source lying adjacent the panel, and having at least one surface of the panel covered with a plurality of adjacent rows or bands of separate straight lines such that the lines extend at right angles from a side edge of the panel, adjacent the light source, while the rows or bands extend in a direction parallel to the light source.
The problem with this type of prior art display system is that the plurality of lines causes (a) significant absorption of light thereby adversely reducing illumination, and (b) is very expensive to manufacture.
Prior art systems of this latter type also exhibit a phenomenon known as line banding. For example, the applicants have found that a panel which has a series of lines extending perpendicular to a light source in rows printed thereon will produce an undesirable illuminated pattern of alternating bright and dark lines.
It has also been found by the present applicants that the prior art series of lines fails to effectively illuminate peripheral edges of a display panel.
One object of the present invention is to provide an alternative illumination assembly which reduces one or more of the aforementioned disadvantages.
The applicants of the present invention have addressed the difficulties faced in prior art systems by way of providing a substrate which contains at leats one continuous interconnecting single line matrix embedded on or within one or both surface(s) of the substrate so as to effectively evenly distribute light across said one or both surface(s).
In one aspect the present invention includes an illuminated sign display assembly including:
a transparent substrate having two oppositely facing surfaces separated by a surface forming an edge between said oppositely facing surfaces; and
a light source on or adjacent to said edge for transmitting light between said opposite facing surfaces of said substrate;
characterised in that at least one of said oppositely facing surfaces of said substrate has applied thereon at least one continuous line forming an interconnecting cellular matrix extending substantially over said one or both oppositely facing surfaces.
The applicants have found that the sign display assembly of the present invention enables even distribution of transmitted light and effectively illuminates the entire panel even at distances remote from the light source. The applicants have also found that their single continuous line matrix effectively illuminates all peripheral edges of a substrate on which the line has been applied and requires a substantially thinner substrate than the prior art thereby obviating cost and weight problems.
In a second aspect of the invention there is disclosed a method of illuminating a sign display assembly, said sign display assembly including:
a transparent substrate having two oppositely facing surfaces separated by a surface forming an edge between said oppositely facing surfaces; and a light source on or adjacent to said edge for transmitting light between said opposite facing surfaces of said substrate;
said transparent substrate having applied thereto, on at least one oppositely facing surface, at least one continuous line forming an interconnecting cellular matrix extending substantially over said at least one oppositely facing surface;
activating said light source adjacent said edge so as to transmit light between said surfaces thereby illuminating said substrate.
It is preferred that the at least one line is applied to at least one surface of the substrate in a single continuous movement.
Because the present application does not include an arrangement containing a series of separate lines, the problem of light absorption and line banding associated with the prior art does not occur.
Preferably the interconnecting cellular matrix is formed by a single continuous line. The continuous line preferably extends in a direction perpendicular and parallel to said light source. In this preferred aspect the interconnecting cellular matrix forms an array of cells of generally rectangular or square geometry.
Preferably the interconnecting cellular matrix comprises an alternating series of open and closed cellular structures formed from said single continuous line substantially adjacent said edge.
In an alternative embodiment it is preferred that the interconnecting cellular matrix comprises a continuous series of closed cellular structures substantially adjacent said edge.
Preferably an interconnecting cellular matrix formed by a single continuous line consists of an even number of cells extending in directions both parallel and perpendicular to said light source. In this embodiment the geometry of cells formed by the interconnecting line matrix is substantially square.
More preferably the interconnecting cellular matrix formed by the single continuous line has an uneven number of cells in any one or both direction(s) perpendicular and parallel to the light source. In this embodiment it is understood that the number of cells formed in a direction parallel or perpendicular to the light source can progressively increase in frequency in any one or both direction(s). Hence the geometry of the cells formed by the line may change or become distorted as the frequency of cells changes.
Most preferably the frequency of cells formed by the interconnecting cellular matrix progressively increases with increasing distance in a direction perpendicular to the light source. The applicant has found that by increasing the frequency of cells in the above manner enhanced luminosity is achieved at surfaces remote from the light source.
The present applicants have found that their interconnecting matrix formed from a single continues line is able to significantly improve distribution of light illumination evenly across the surface(s) of a substrate.
Preferably the illuminated sign display assembly comprises more than one light source.
Preferably the transparent substrate is any described geometry selected from but not limited to planar, radial, undulating, triangular or curved.
Preferably the transparent substrate is selected from an acrylic plastic, polycarbonate, glass or any clear material through which light can be transmitted.
Preferably the substrate has a thickness of less than 10 mm. More preferably the substrate has a thickness within the range of between 4.5 mm to 6 mm. It is understood by the applicants that the application of a single line to the substrate to form an interconnecting cellular matrix increases luminosity to such an extent that the thickness of the substrate and associated costs can be significantly reduced.
Preferably at least one continuous line can be applied to one or both oppositely facing surfaces of the transparent panel.
Preferably the illuminated sign display assembly further comprises a prism extending parallel and adjacent to said light source so as to provide a greater surface area through which light may be directed into the substrate.
Preferably the light source is positioned on or above one of said oppositely facing surfaces adjacent said linear edge.
Preferably the interconnecting cellular matrix formed by at least one continuous line is applied to one or both surface(s) of said oppositely facing surfaces by means of, but not limited to, scarring, etching, scratching, painting, sand blasting, screen printing, laser or the like.
Preferably the illuminated sign display assembly further includes a transparent image, poster or hologram.
Preferably the linear edge separating said oppositely facing surfaces of said substrate is provided at an angle to the light source so as to increase the surface area through which light may be transmitted from the light source. More preferably the linear edge is provided at an angle of about 45xc2x0 to the light source.